Cable couplers that couple two tensioned cables together are used in many applications. For example, in underground mining operations a cable roof truss is created in an underground mine passage generally consists of a tensioned cable extending between a pair of embedded roof anchors. Many times, the tensioned cable is made up of two sections which must be joined by a coupler. The construction industry also uses joined cables in a number of applications, such as in column wrapping, ring-tensioning applications, or with barrier cable installations often seen in parking garages.
A first design for a cable coupler is known as a spacer tube, often rectangular in section that has two barrels extending through the coupler. The cables are pulled through the barrels in opposite directions and tensioned. A set of wedge pieces are placed in the barrels adjacent the cables and the cables are released. The cables pull backward under their own tension, drawing the wedge pieces into the barrel. The wedge pieces grip the cables and lock the cables relative to the coupler.
A second design incorporates a curved path for each of the cables. This design, commonly known as the “dog bone” coupler due to the distinctive shape of the coupler, is different than the spacer tube in that the passages for the cables are curved to reduce sharp edges and to more evenly distribute the forces along the cable. Again, after the cables are tensioned and released, the cables and the retaining wedges are drawn into the tapered passageways of the coupler, drawing the wedge pieces into progressively greater contact with the cables so that the wedge pieces grip and lock the cables relative to the coupler.
In both of the aforementioned designs, the user must first insert both cables through the barrels of the coupler and then, using a tensioner, place the cables under tension. The wedge pieces must be manually placed adjacent the cables and in the tapered portion of the barrels. Unfortunately, these loose wedge pieces can easily fall to the ground during installation, and the wedge pieces may be lost in the darkness of a mine passage. Valuable time may be lost looking for and recovering any dropped or lost wedge pieces. To alleviate this often-encountered problem, suppliers generally provide extra wedges with the cable coupler. However, even if the wedge pieces are not lost, time and manual dexterity are required to insert the wedges into the coupler, which may have to be accomplished in a cold and/or dark setting.
While the disclosure is susceptible to various modifications and alternative constructions, certain illustrative embodiments thereof have been shown in the drawings and will be described below in detail. It should be understood, however, that there is no intention to limit the disclosure to the specific forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and the equivalents falling within the spirit and scope of the invention as defined by the appended claims.